Communication begins with language, the distinctive ability which has made possible the evolution of human society. With language any message, no matter how complex, can be conveyed between people over a limited distance - within a room or place of assembly, or across a short open space. In modern times 'town criers' hold an annual contest to discover which of them can shout a comprehensible message over the greatest distance. The world record is less than 100 metres. Already, at that short range, a more practical alternative is to run with the message.

The history of communication is mankind's search for ways to improve upon shouting.

When running with a message, to convey it in spoken form, it is safer to do it oneself. Sending anyone else is unreliable, as the game of Chinese whispers demonstrates. So another requirement for efficient communication is a system of writing.

Messages carved on stone pillars communicate very well across time, down through the centuries, but they are an inefficient method of communicating across space. The message reads only within reading range; its recipients must travel to receive it. The system is altogether more efficient if it is the message which travels. This requires yet another ingredient in the communication package - a portable writing material such as papyrus.

There are forms of long-distance communication not based on words. The smoke signals used by American Indians (above all perhaps in westerns) are of this kind. So are bonfires lit in succession on a line of hilltops. But such devices are only capable of conveying very limited pre-arranged signals, such as 'danger' or 'victory'.

Some non-verbal systems are more sophisticated. The whistled language of Gomera, in the Canary islands, is used to communicate across deep valleys. It is well adapated to the islanders' immediate needs, but would be incapable of sending this paragraph as an accurate message. For communication of this kind writing remains indispensable.

Post haste: 6th century BC

The sending of written messages is a standard feature of government in early civilizations. Much of our knowledge of those times derives from archives of such messages, discovered by archaeologists.

There is great advantage to a ruler who can send or receive a message quicker than his rivals. In the estimation of the ancient world the most efficient postal service is that of the Persians. Put in place by Cyrus in about 540 BC to control his new empire, the largest yet known, it is much improved upon by Darius a generation later.

Imperial communication: 522-486 BC

Darius extends the network of roads across the Persian empire, to enable both troops and information to move with startling speed. At the centre of the system is the royal road from Susa to Sardis, a distance of some 2000 miles (3200 km). At intervals of a day's ride there are posting stations, where new men and fresh horses will be available at any moment to carry a document on through the next day's journey. The Greek historian Herodotus marvels at these Persian couriers.

By this method a message can travel the full distance of the road in ten days, at a speed of about 200 miles a day. A similar road goes down through Syria to the Mediterranean coast and Egypt. Another goes east to India.

Many different tongues are spoken in the Persian empire, from Egypt to India. But all the official messages travelling on the imperial roads are in one language, Aramaic. This Semitic tongue, deriving from a tribe in northern Syria, first spreads through Assyria. Then Babylonian merchants carry it further afield until, by the 6th century, it is in general use as a Lingua franca throughout Mesopotamia.

As a language for the Persian civil service, Aramaic also has a practical advantage. It uses the Phoenician alphabet, a language to which it is related. So its letters can be written on papyrus (easily portable) instead of needing to be pressed with a cuneiform stylus into wet clay.

Speeding up the messenger: 2nd - 11th century

Until recent centuries, the only way to increase the speed of communication has been to improve the speed of the messenger. This depends on good roads, fast riders and well provisioned staging posts at which fresh men and horses are always available. The network of Roman roads makes communication steady and reliable, but it is unlikely that it is faster than the delivery system perfected by the Persians - on the terrain of steppe and plateau, across which horsemen can gallop with fine abandon.

However one major improvement in the speed of communication is recorded in the Middle East, where in certain circumstances a simpler messenger is substituted for the horse and rider.

Pigeon post: from the 11th century

Domesticated pigeons are first developed in ancient Egypt, and the pigeon loft or dovecote subsequently becomes a living larder for many communities - such as medieval monasteries. In Baghdad, in the 11th century, the idea first occurs of making use of the tendency of certain pigeons to fly straight home from wherever they may be.

A rapid one-way postal service (always back to base) becomes possible. By selective breeding of suitable birds, the homing pigeon is developed. The swiftest and most wide-ranging conqueror of medieval history, Genghis Khan, sees the obvious potential. Pigeons carry swift news of each new conquest to his homeland in Mongolia.

But the rapid and widespread dissemination of a message must await the development of printing.

Scholars in the east have had the benefit of printing for many centuries, enabling holy and learned texts to be more widely possessed. But the very late arrival of printing in the west proves to be of much greater significance. The development by Gutenberg in Germany of movable type happens to coincide with the Renaissance, a time of great vigour in European culture.